(1) Field of the Invention:
The present invention generally relates to a magnetic tape apparatus and method for reproducing data from or recording data onto a magnetic tape, and relates more particularly to an improvement in a magnetic tape apparatus and method wherein a tape-driving capstan motor is controlled during its starting acceleration in such a way as to minimise or eliminate slippage between the tape and the tape-driving capstan, and so to minimise or eliminate damage that would otherwise be caused to the tape.
The invention is most particularly concerned with magnetic tape apparatus for the storage and reproduction of digital data for computer systems or the like, but is also applicable to apparatus for other types of digital or analogue data, including video and/or audio data.
(2) Description of the related Art:
A data tape recorder system is a particular form of magnetic tape apparatus. A data tape recorder system typically employs a tape cassette in which a housing contains two rotatably mounted tape reels onto which a length of magnetic tape is wound. During operation of the data tape recorder system either to record data signals onto the magnetic tape or to play back data signals previously recorded on the magnetic tape, the tape is driven at a constant linear speed by means including a capstan rotated at a constant speed by a capstan motor, the tape being pressed against the periphery of the capstan by means of a pinch roller. At commencement of operation, the tape and the tape-driving capstan have to start up from standstill and accelerate to normal operating speed. If rotational acceleration of the capstan at start up is excessive, there will be a very considerable initial excess of capstan speed over tape speed which results in the capstan skidding across the tape, and the tape may be damaged by the capstan spinning with respect to the tape. Such spinning and skidding causes wear and abrasive damage to the tape, and may degrade the tape recorder with internal debris. Such damage is particularly likely in prior art tape recorder systems where the capstan accelerates without special control of acceleration at start up.